A few points that come to mind:
1. As Azelor said, the amount of rivers and streams shown is overkill unless this is specifically a hydrologic map. It gets difficulty to identify the main ones, and that will only get worse if you start adding in other information (settlements, roads, borders, etc).
2. Your mountain ranges seem unusually discontinuous. You've got what I assume are meant to be pretty high mountains, but they're repeatedly broken by passes that dip down to the lowest (green) elevation level. I'd say the baseline elevation for the mountainous region should be significantly higher than what you see on the plains.
3. I personally like the hillshading because then you can use the color to represent something else (vegetation, political units, etc.). But I admit I have a pet-peeve dislike of the green-yellow-brown elevation color scheme.